I´ve been reading some posts and it looks like I will need this development packege if I want to compile PHP with the new GMP library, am I right?

I don´t know if it was right but I downloaded the latest devepment package and when I think about it I have XAMPP for linux 1.4.13, do I have to download and unpack the same version for this devepment package?

Can anyone tell me how I use this development package in order to compile PHP with the new library??